1. Field of the Invention
This invention relates generally to cleaning apparatus, and more particularly to self contained apparatus for using cleaning fluids to automatically clean small parts or devices.
2. Discussion of Related Art
It is known that machine parts can be cleaned using containers, in which the machine parts to be cleaned are lowered into a washing liquid. In DE-GM 1 962 757, washing liquid is taken from a reservoir by means of a pump, sprayed onto the parts to be cleaned and then, after collection at an outlet, returned to the reservoir via filters. In the first of these cleaning systems, the cleaning effect is obtained solely by partial dissolution and softening and is therefore inadequate for many applications. Also, the liquid is difficult to regenerate. In addition, because the washing compartment is substantially filled with the cleaning liquid, the arrangement is undesirably heavy. Although the arrangement according to DE-GM 1 962 757 has moderate dimensions and is lighter in weight than the first system, the open spraying of the cleaning liquid limits the intensity of the cleaning jets. Even if the liquid is sprayed with little energy, there is the problem of unwanted odor emission and the further problem of serious soiling contamination of the surroundings through rebounding liquid droplets.
In ultrasonic cleaning, which has frequently been proposed, sensitive parts are subjected to severe mechanical stressing which they are often incapable of withstanding. Thus, electronic components and type wheels of printers react to ultrasonic cleaning by developing hairline cracks so that they fail prematurely. The washing liquid required in large amounts soils quickly and involves both considerable supply costs and disposal problems.
An arrangement operated with a cleaning preparation which, for example, dissolves fats and resins, but does not affect plastics and rubber, is showing in DE-OS 38 02 486. The compact arrangement can be made transportable and does not require fixedly installed vent pipes. However, there is a need to simplify the cleaning process and to save labor. In addition, it has been found that, in a number of cases, mobile problem-free cleaning systems are limited in use by inadequate regeneration of the cleaning liquid collected, forcing the use of only fresh cleaning liquid, and causing reliability problems when working in closed rooms.